Covered immunity could take months: new research clarifies previous findings

A new study suggests that the body’s immune response to the new coronavirus may take at least eight months from the onset of symptoms from the initial infection.

The duration of immunity to Covid-19 has been the subject of pandemic research, and studies to date have yielded various results. In July last year, a study suggested that immunity could be lost in a few months. As Indian Express reported then, researchers at King’s College London drew this conclusion from an observed decrease in antibody levels in patients recovered with Covid-19 over time – from a “strong level” to 60% of study participants during peak infection at only 16.7%, keeping that potency level 65 days later. While that study suggested that patients recovering with Covid-19 are likely to remain susceptible to re-infection, the new study suggests that almost all Covid-19 survivors have the immune cells needed to fight reinfection.

The study, published in the journal Science, is based on blood test analyzes from 188 patients. “Our data suggest that the immune response exists – and remains,” said Alessandro Sette of the La Jolla Institute (LJI), who led the study with Shane Crotty and Daniela Weiskopf, in a statement issued by the LJI.

“We measured antibodies, memory B cells, helper T cells and killer T cells at the same time. As far as we know, this is the largest study ever conducted for any acute infection, which measured all four components of immune memory, ”LJI was quoted as saying by Crotty.

The findings could mean that Covid-19 survivors have protective immunity against serious diseases caused by the SARS-CoV-2 virus for months, maybe years, after infection, the researchers said. Their study addresses concerns arising from Covid-19 data from other laboratories, which have shown a dramatic decrease in Covid-specific antibodies over time.

According to the researchers, the decrease in antibodies is very normal. “It simply came to our notice then. They have a first phase of growth and, after this fantastic expansion, finally the immune response contracts to some extent and reaches a state of equilibrium “, said Sette.